Wearscience.com has some brilliantly designed t-shirts which hijack the "teach the controversy" phrase used by creationists in the united states. http://controversy.wearscience.com/
I'm particularly impressed with the two dinosaur designs. They were the first that I saw and I was actually unsure what side of the debate had produced the designs. I would be unsurprised to find the triceratops pulling the plow at the creation museum gift shop. http://creationmuseum.org/
I would have posted them even if the designs had been produced by the political right. They made me think long enough about what they were trying to say that I am duly impressed no matter who made them.
On a side note, does it bug anyone else that extreme conservatives get associated with the word "right" which can also mean correct?